Field of the Invention
There is a problem in the prior art to provide a metal coating firmly adhered to polyolefin film surfaces. One approach to solving this problem has been to modify the surface of the polyolefin by various surface oxidation processes. Another process to improve the bond strength between the metal coating and the film involves the application of an adhesive layer to the surface of the film. For example, U.S. Pat. No. 3,567,487 describes the use of a prime coat such as a dispersion or solution of an acid containing polymer such as carboxylated butadiene polymers and maleic anhydride modified atatic poly- propylene polymers.
The prior art also calls for the use of a slip agent to reduce the coefficient of friction of the film to aid in machine handling of such film. Such slip agents may be incorporated in the film. Typical slip agents may be fatty acid amides such as stearamide or oleamide.